A few random I/O proposals

["Aubrey Jaffer" <jaffer@martigny.ai.mit.edu>]

      My functions return #f for failure.  Despite dire warnings from
      several people on comp.lang.scheme, I have NEVER been burnt by this
      (and I make lots of mistakes).

   I believe you since I have not been bitten myself on my own code
   because I am compulsive about testing return values (in C).  However,
   I've had to debug and fix enough broken C/Unix software (which uses
   this method) written by other people that I do not believe it is an
   acceptable solution for any language, and certainly not for Scheme.

Most, if not all, Schemes signal error if a #f is passed instead of a
port, whereas C just goes crazy.  Scheme's type system provides
detection of this error.  That is why it is easier to find an unopened
port in Scheme than in C.  Comparison with C is not very applicable
here.